Lathe tool-holder.



B. F. ENNIS.

LATHE TOOL HOLDER.

APPLIOATION FILED 00w. 20,1905.

91 7,029 Patented Apr. 6, 1909.

A ATTORNEY.

PATENT BENJAMIN F. ENNIS, OF SYRACUSE, NEW YORK, ASSIGNOR TO JOHN N. SGISM, OF SYRACUSE, NEW YORK.

LATHE TOOL-HOLDER.

Specification of Letters Patent.

Patented April 6, 1909.

Application filed October 20, 1905. Serial No. 283,688.

To all wlumt it may concern:

it known that l, BENJAMIN F. ENNIs, a citizen of the United States, and resident of Syracuse, in the county of Onondaga, in the State of New York, have invented new and useful Improvements in Lathe 'iool-Holders, of which the following, taken in connection with the accompanying drawings, is a full, clear, and exact description.

This invention has special reference to the class of tool holders which are designed to be supported on the tool-post of a lathe, upon which support it may be placed in various positions to present the tool at any desired angle in relation to the axis of the lathe.

The object of the invention is to provide a tool-holder of the aforesaid class which shall be equipped with a tool-holding aw possessed of superior strength and efiiciency of firmly gripping and securely holding a cylindrical tool of minimum diameter as well as tools of greater diameters without danger of unduly straining the said jaw. And the obj ect furthermore is to provide the tool holder with a jaw having a pluralit g of sharp toolgripping ribs disposed to allow a perfect or uniinpai. gripping rib thereof to be placed in operative position previously occupied by an injured gripping-rib of said jaw. And to that end the invention consists in the improved construction and combination of parts hereinafter described and illustrated in the accompanying drawings in which Figure 1 is side View of tool-holder enibodying my invention; 2 is a plan view of the same, Fig. is an inverted plan view; Fig. l is a view of the ioohholding head; Fig. 5 is a longitudinal section on the line X TM in llig. l; and, Fig. 6 is a detached side View of the adjustable rool-gripping aw or block.

-arepresents the tool-receiving head of the tool-lwlder, and -a the supporti1g-ar1n which. extends frmn the said head and is mounted on the tool-post. (N ot shown.) The head ais forms with an aperture Z) which extends longitudinally through said head and parallel with the shank of the tool to be held therein. Said aperture is formed with parallel straight side-walls -cc united at both ends by transverse walls d-d-, on one of which the tool t (indicated by dotted lines) is seated. Said tool-seat is thus stationary or fixed in the holder and is preferably of the form of a V-shaped groove e to altord two bearings for a cylindrical tool, the inclinations of said bearings serving to retain the tool central between the side-walls cc of the aperture b. The opposite transverse wall c is formed with a screw-threaded bore t in a line central between the side walls c-c and parallel therewith. Through the said bore passes a set-screw h for operating the adjustable tool-gripping jaw f which extends longitudinally through the aperture b and is formed with parallel sides fitted closely to the side-walls cc to properly sustain the jaw laterally in the aperture of the toolholder and prevent the said. jaw from turning therein. The jaw is detached from the set-screw h which merely bears on the back ofthe said jaw at a point central between the side walls -cc of the aperture 7)- and consequently diametrically opposite the center of the tool-seat -c. The jaw -f is formed with a longitudinal toolgripping edge or rib g central between the side-walls ccof the aperture band presented toward the tool-seat -eat a point diametrically opposite the rib g-- which is in a direct line passing through the axial center of the screw. By turning the aforesaid set-screw in a direction to force it inward, it is caused to press the jaw into ongagement with the tool tsupported on the stationary seat c. In the said engagement the rib -g bites the tool on a line central between the side walls c-c of the tool-holder head and parallel therewith and thus effectually prevents the tool from turning in the holder. I preferably form the jaw f hexagonal and thereby provide the jaw with six of the aforesaid ribs and at the same time increase its depth between the bearing of the set-screw and the rib presented toward the tool-seat. The said increased depth of the jaw imparts thereto greater strength for resisting breakage by pressure of the set-screw which bears on the back of the jaw in a line with the reinforcement thereof. In a jaw of the aforesaid shape, I "form a flattened indentation r in the edge or rib 9* for a bearing of the set-screw as shown in Fig. 5. The grooved tool-seat c is of the same width as the aperture and shaped to correspond to angles or" the hexagonal jaw f as shown in Fig. at ofthe drawings. A screw n llt) passing through a transverse slot -l in one of the side-wa ls cand engaging a socket j in the side of the jaw f serves to prevent said jaw from slipping out of the aperture b.' By forming both transverse walls d-d of the aperture b with V-shaped grooves ee and with screw-threaded bores 'ii and forming the jaw f hexagonal as shown in Fig. l, the tool-holder is adapted to be used in reversed positions and is thus more convenient in its use.

' To enable the tool-holder to better resist the torsional strain transmitted to it in the operation of the tool, I form it with broad bearing-surfaces ss by which it rests on the tool-post or slide-rest of the lathe and is clamped thereon in the usual and well known manner.

What I claim as my invention is 1. A lathe-tool holder having its head pro vided with an a erture formed with parallel straight side-walls, a grooved V-shaped toolseat in one of the transverse walls of the aperture and a threaded bore in the center of the opposite transverse wall, a jaw of hexagonal shape in cross-section disposed in the aperture and adjustable to present different corners thereof toward the tool-seat, and a set-screw passing through the aforesaid bore and bearing on the jaw in a line passing through two diametrically opposite corners thereof as set forth and shown. 7

2. A lathe-tool holder having the tool-receiving head formed with an aperture extending therethrough, the side-walls of said aperture being straight and parallel and the transverse walls being formed with longitudinal V-shaped grooves, threaded bores extending through the transverse walls central of and at right angles to the aforesaid grooves, and a slot through one of the side-walls at right angles to the transverse walls, a toolgripping block shaped hexagonal in crosssectien disposed in the aforesaid aperture movable toward and from the transverse walls thereof and guided by the side-walls and provided with a threaded socket in its side, a screw passing through the slot in the side-wall of the aperture and inserted into the socket of the tool-gripping block, and a set-screw passing through the threaded bore of one of the transverse walls and bearing on the t0ol-gripping block as set forth and shown.

BE JAMIN F. ENNIS.

Witnesses i J. J. LAASS, L. H. FULMER. 

